Related papers: Neutrinoless double-beta decay at colliders: inter…
We examine lepton number violation (LNV) in theories with a saturated black hole bound on a large number of species. Such theories have been advocated recently as a possible solution to the hierarchy problem and an explanation of the…
We demonstrate the ability to measure the CP-phase of a Higgs boson state by looking at the decays of heavy, Majorana neutrinos in the process $pp \to H \to N N$ at the LHC. This is shown for signals with both opposite-sign ($l^{\pm}…
We use the LHC Higgs data to derive updated constraints on electroweak-scale sterile neutrinos that naturally occur in many low-scale seesaw extensions of the Standard Model to explain the neutrino masses. We also analyze the signal…
Double beta decay is indispensable to solve the question of the neutrino mass matrix together with $\nu$ oscillation experiments. Recent analysis of the most sensitive experiment since nine years - the HEIDELBERG-MOSCOW experiment in…
Observation of the neutrinoless double beta decay ($\0n$) has established that there is lepton number violation in nature and the neutrino masses are Majorana in nature. It also gives the absolute mass of the neutrinos and discriminates…
Small neutrino masses confirmed in the neutrino oscillation experiments indicate the need for new physics beyond the standard model. Seesaw mechanism is an interesting way to extend the standard model for explaining the neutrino masses. In…
Same-sign lepton colliders offer a promising environment to probe lepton number violation. We study processes that change lepton number by two units in the context of Majorana heavy neutral leptons and neutrinophilic scalars at…
In this paper we investigate how well the nature of heavy neutral leptons can be determined at a future lepton collider, after its potential discovery. Considered in a simplified model are prompt decays of the neutrino in the mass range…
Majorana neutrino mass models with a scale of lepton number violation (LNV) of order TeV potentially lead to signals at the LHC. Here, we consider an extension of the standard model with a coloured octet fermion and a scalar leptoquark.…
Understanding the origin of lepton number violation is one of the fundamental questions in particle physics today. Neutrinoless double beta decay provides a way in which this violation can be tested. In this article, we derive the form of…
In order to address the observation of the neutrino oscillations and the metastability of the Standard Model, we extend the fermion sector with two right-handed (i.e. sterile) neutrinos, and the scalar sector of the SM with a real scalar,…
The low-energy neutrino physics constraints on the TeV scale type I see-saw scenarios of neutrino mass generation are revisited. It is shown that lepton charge (L) violation, associated to the production and decays of heavy Majorana…
We examine the observability of heavy neutrino (nu_h) signatures of a U(1)' enlarged Standard Model (SM) encompassing three heavy Majorana neutrinos alongside the known light neutrino states at the the Large Hadron Collider (LHC). We show…
The discovery of lepton number violation (LNV) at the LHC would have profound consequences for the viability of high-scale leptogenesis models. As an example, we discuss the case of observing a signal with two same-sign leptons, two jets…
Neutrinoless double-beta decay searches play a major role in determining the nature of neutrinos, the existence of a lepton violating process, and the effective Majorana neutrino mass. The Majorana Collaboration proposes to assemble an…
We study the purely leptonic decays of $W^\pm \to e^\pm e^\pm \mu^\mp \nu$ and $\mu^\pm \mu^\pm e^\mp \nu$ produced at the LHC, induced by sterile neutrinos with mass $m_N$ below $M_W$ in the intermediate state. Since the final state…
We discuss same-sign dilepton production mediated by Majorana neutrinos in high-energy proton-proton collisions $pp\ra \ell^+ \ell^{\prime +}X$ for $\ell,~ \ell^\prime = e,~ \mu,~ \tau$ at the LHC energy $\sqrt{s}=14$ TeV. Assuming one…
The Large Hadron Collider provides us new opportunities to search for the origin of neutrino mass. Beyond the minimal see-saw models a plethora of models exist which realise neutrino mass at tree- or loop-level, and it is important to be…
A search for heavy neutral leptons (HNLs) decaying in the CMS muon system is presented. A data sample is used corresponding to an integrated luminosity of 138 fb$^{-1}$ of proton-proton collisions at $\sqrt{s}$ = 13 TeV, recorded at the…
It is well known that there exist many mechanisms that may contribute to neutrinoless double beta decay (0nbb-decay). By exploiting the fact that the associated nuclear matrix elements are target dependent we show that, given definite…